线代,怎么求行列式?4 1 2 41 2 0 210 5 2 0 0 1 1 7
问题描述：
线代,怎么求行列式?
4 1 2 4
1 2 0 2
10 5 2 0
0 1 1 7
答
4 1 2 4 1 2 0 210 5 2 0 0 1 1 7r3-2r1-2r2, r1-4r2 0 -7 2 -4 1 2 0 2 0 -1 -2 -12 0 1 1 7r1r2 1 2 0 2 0 -7 2 -4 0 -1 -2 -12 0 1 1 7r2-7r3,r4+r3 1 2 0 2 0 0 16 80 0 -1 -2 -...